What is the preferred treatment between thrombolysis with alteplase (tissue plasminogen activator) and embolectomy catheter-based intervention in acute stroke management?

Endovascular Thrombectomy is Superior to Thrombolysis Alone for Acute Ischemic Stroke with Large Vessel Occlusion

For patients with acute ischemic stroke due to large vessel occlusion in the anterior circulation, endovascular thrombectomy combined with IV alteplase is the preferred treatment, providing a 50% increase in good functional outcomes compared to medical therapy alone. 1

Treatment Algorithm Based on Time and Vessel Occlusion

For Patients WITHOUT Large Vessel Occlusion (LVO)

Within 0-3 hours of symptom onset:

• Administer IV alteplase 0.9 mg/kg (maximum 90 mg) with 10% as bolus over 1 minute, followed by 90% over 60 minutes (Grade 1A recommendation) 1, 2
• This provides 154 more favorable outcomes per 1,000 patients treated 2

Within 3-4.5 hours of symptom onset:

• Administer IV alteplase using the same dosing protocol (Grade 2C recommendation) 1, 2
• This provides 69 more favorable outcomes per 1,000 patients treated 2

Beyond 4.5 hours:

• Do NOT administer IV alteplase (Grade 1B recommendation against use) 1, 3

For Patients WITH Large Vessel Occlusion (LVO)

The evidence dramatically shifted after 2015 when multiple landmark trials demonstrated thrombectomy superiority:

Within 6 hours of symptom onset:

• Administer IV alteplase immediately if eligible (do NOT delay for thrombectomy evaluation) 4
• Proceed directly to endovascular thrombectomy WITHOUT waiting to assess IV alteplase response 4
• This combined approach increases good functional outcomes (mRS 0-2) with RR 1.50 (95% CI 1.37-1.63) 5
• Reduces mortality with RR 0.85 (95% CI 0.75-0.97) 5

Within 6-24 hours with favorable imaging:

• Use advanced imaging (CT perfusion or diffusion-weighted MRI) to determine thrombectomy eligibility 4
• Proceed with thrombectomy if salvageable tissue is present 4

Critical Distinction: 2012 vs 2015 Guidelines

The 2012 American College of Chest Physicians guidelines suggested AGAINST mechanical thrombectomy (Grade 2C), stating uncertain benefits. 1 However, this recommendation became obsolete after the 2015 publication of five major randomized trials (MR CLEAN, ESCAPE, SWIFT PRIME, EXTEND-IA, REVASCAT) that definitively proved thrombectomy superiority. 1

The 2015 AHA/ASA focused update reversed this position entirely, establishing endovascular thrombectomy as standard of care for LVO. 1 These trials showed:

• Recanalization rates of 72-88% with modern stent retrievers 1
• Symptomatic ICH rates similar between thrombectomy (4.4%) and control (4.3%) groups 1
• Number needed to treat of approximately 3-4 patients for one additional good outcome 5

Why Thrombectomy Outperforms Thrombolysis Alone for LVO

IV alteplase has extremely poor recanalization rates for large clots:

• Clots ≥8mm in length have minimal response to IV thrombolysis alone 6
• Proximal MCA and ICA occlusions rarely recanalize with IV therapy alone 6

Thrombectomy with stent retrievers achieves:

• 83% successful recanalization vs. near-zero with IV therapy alone for high clot burden 6
• Median mRS at 90 days of 3 vs. 5 (p<0.01) compared to thrombolysis alone 6
• Mortality reduction from 40% to 7.5% at 90 days in high clot burden strokes 6

Practical Implementation

Do NOT use the following outdated approach:

• Giving IV alteplase and "waiting to see" if the patient improves before considering thrombectomy 4
• This wastes critical time and worsens outcomes 4

Instead, use this parallel pathway:

1. Obtain CT angiography immediately to identify LVO 1, 4
2. Administer IV alteplase if within 4.5 hours and eligible 4
3. Simultaneously activate thrombectomy team if LVO confirmed 4
4. Proceed directly to angiography suite without reassessing clinical response 4

Special Considerations for Intraarterial Thrombolysis

For patients who do NOT meet IV alteplase eligibility criteria but have proximal vessel occlusion:

• Consider intraarterial alteplase within 6 hours of symptom onset (Grade 2C) 1, 2
• This is particularly relevant for patients beyond the 4.5-hour IV window 1

Adjunctive intraarterial alteplase during thrombectomy:

• Safe when used during mechanical thrombectomy procedures 7
• Shows trend toward improved recanalization without increased hemorrhage risk 7
• Equivalent rates of hemorrhagic conversion and mortality compared to thrombectomy alone 7

Common Pitfalls to Avoid

Blood pressure management is critical:

• Lower BP below 185/110 mmHg BEFORE initiating IV thrombolysis 4
• Failure to control BP increases hemorrhagic transformation risk 4

Hyperglycemia substantially increases hemorrhage risk:

• Glucose >11.1 mmol/L associated with 36% symptomatic ICH risk 4
• Correct hyperglycemia before thrombolysis when possible 4

Extended window (3-4.5 hours) has additional exclusions:

• Age >80 years, oral anticoagulant use (regardless of INR), NIHSS >25, or history of both stroke and diabetes 4

The 2012 recommendation against thrombectomy is obsolete:

• Ignore any guidance suggesting thrombectomy has "uncertain benefits" 1
• This was based on older-generation devices (MERCI retriever, Penumbra) before modern stent retrievers 1